All sails are made and guaranteed to conform with class rules. All sails have taped and sewn seams. Sail panels are warp oriented, in the load direction, and are alternated, front to back, to maintain vertical partitioning. The foot of each sail is stabilized with an additional material layer to help prevent curling. Included are draft stripes, telltales, luff pockets on both sails, battens, plus an installed jib luff wire. Standard sails have starburst reinforced grommeted corners made of black, red, white, blue, green, yellow hot pink or fluorescent orange Dacron ripstop. Full roach sails (US1M, S/B, Soling 50 etc.) have layered Dacron patch corner reinforcements. Nylon reinforced tie points are included on the mainsail luff as appropriate.

Extensive testing by Sirius Sails have shown that the type of sail cloth has almost no impact on performance, given that the load limits of the material are not exceeded. Generally, heavier sail cloth is more stable in all load directions than lighter sail cloth, is less flexible, but will provide the longest racing life. Lighter cloth weights are more flexible and respond to light air more readily, making them easier to read, but do not provide the longevity of heavier cloth. Most standard Sirius Sails suits pair a heavier weight material main with a lighter material jib to optimize responsiveness and longevity. Details and uses for each type of cloth are:

GTS TriSpi 40- .9 oz mylar (6μ PET) with scrim in the warp and fill directions. Medium/high flexibility with great strength when warp load oriented. Suitable for all purpose use.

GTS TriSpi 50 - 1.2 oz mylar (9μ PET) with scrim in the warp and fill directions. Strongest, but least flexible of the TriSpi materials. Suitable for larger sails and high wind sails.

CPM 505 - .75 oz mylar film with an omni-directional fiber backing that provides excellent omni-directional strength and medium flexibility. This material is quite expensive and the fiber side is hydroscopic, but it's directional stability makes an excellent sail. Best suited for mainsails on all model yacht sizes.